Alber Cellcorder CRT-300, Руководство пользователя

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Application Note CC-001
80
TEMPERATURE AND INTERNAL RESISTANCE
Being aware of the effect of temperature on internal resistance is
important. Figure 7, for a typical AGM VRLA cell, clearly shows rapid
internal resistance and impedance increases below temperatures of about
45

F. 8
In temperate climates, VRLA cells in
unconditioned temperature
environments may show considerable internal resistance variation
between quarterly measurements. Recording of the ambient temperatures
at the time of measurement will might save you further testing and false
alarms. Similarly, cells chilled by air conditioning exhibit higher
readings than their sheltered neighbors. If possible, try to re-direct the air
flow.
THE CELLCORDER
The Cellcorder is invaluable in determining what a battery or cell’s
internal resistance is and in helping to identify abnormal conditions and
normal aging.
While a battery or cell is on-line, it accurately and
repetitively measures the internal resistance using DC techniques. The
AC filtering currents, stray 60 hertz fields, noise and normal float
currents have virtually no effect on its readings.
The authors can’t help but wonder what earlier researchers could have
accomplished if they had access to microprocessor and solid state
technology. The microprocessor of the Cellcorder permits it to not only
control measurements, but to also precisely time the readings and
performs calculations. To boot, it can tell whether a reading is valid and
then records the results.